On Lampedusa, the Italian island closest to the Libyan coast where many migrant boats arrive, the anti-immigration party pocketed 45.8 percent of the vote in Sunday's election.
It also scooped 44 percent of votes in Ventimiglia, where migrants attempt to cross over into France undetected, and 41 percent in Bardonecchia, the last station stop for those willing to risk frostbite on the mountain crossings.
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In Calabria, the heartland of the League's coalition partner — the anti-establishment Five Star Movement (M5S) — Salvini's party outdid the competition in Riace, a town acclaimed by the left as an example of migrant integration.
Former mayor Domenico Lucano, the man behind the scheme, is being prosecuted for allegedly aiding illegal immigration. The League took 30 percent of the votes in the small town, compared to 26 percent for the M5S and 17 percent for the centre-left Democratic Party (PD), which supports Lucano.
But Lampedusa's Pietro Bartolo, a doctor who has dedicated years of service to helping migrants and who ran as a PD candidate for Sicily and the islands, appeared to have been elected to the European parliament, exit polls showed.